net.tcp.service[https] check is wonky

[kkaos]

I'm using the net.tcp.service[https] check to make sure port 443 is open on some of my web servers. In particular, I have a production web server and staging web server. The check works and returns that the port is UP (listening) on the production web server; however, the check says the port is DOWN on the staging web server, when, in fact, the port is UP.

Both servers are running CentOS 6.5 and Zabbix agent 2.0.11. I've already verified that SELinux is not blocking this access.

Should I file a bug report? If not, maybe there's something I'm missing? Please advise.

Thanks!